This invention relates generally to medical prosthetic systems, and particularly to implantable devices which make use of a valve to control inflation of a prosthesis.
Specially adapted valves have been used in the construction and operation of various inflatable prosthetic devices designed for medical implantation. Such devices have been designed to aid in the treatment of urological disorders including erectile impotence, urinary incontinence, and fecal incontinence. A device usable to cure erectile impotence is described by Robert Buuck in U.S. Pat. No. 3,954,102. The patent discloses a check valve including a Teflon ball housed within a silicone rubber tube and a bypass valve making use of similar components. The bypass valve opens when deformed by being squeezed laterally. Another patent by the same inventor (U.S. Pat. No. 3,863,622) discloses an implantable device suited to controlling either the flow of urine or fecal waste. Check valves which make use of a helical coil spring are shown therein. A valve usable in controlling an inflatable penile prosthesis is disclosed by Aurelio Uson in U.S. Pat. No. 4,009,711. Uson shows a valve which acts as a check valve in one direction and may be squeezed gently to allow reverse fluid flow.
Prior art valves adapted for physiological drainage, such as Schulte, U.S. Pat. No. 3,758,073 have relied upon lateral compression forces to allow reverse flow. Such valves cannot be placed in remote locations since they must be accessible to the user. Also, such valves are difficult for the user to locate and hold in place. If a large amount of lateral compression or a large amount of squeezing is required for the operation of implantable valves, nearby living tissues which are subjected to high stresses during the compression or squeezing may become inflamed and damaged. Also, high stresses will be caused in the valve structure thus encouraging fatigue failure and foreshortening the useful life of the valve. In many of the prior art devices, the patient must be instructed not to press the release valve too forcefully as excessive pressure will temporarily close rather than open the valve.